关键词: 水下修补材料; 混凝土裂缝; 快凝快硬硫铝酸盐水泥; 水下抗分散性;

Abstract: Underwater concrete cracks are difficult to repair as they are in a saturated environment constantly.Therefore, it is of great significance to develop a repair material suitable for underwater construction.To this end, a new type of environment-friendly cement-based underwater rapid repair material was developed by using rapidly solidification sulphoaluminate cement as the main cementing material and PAM as the flocculating agent.The core components and proportion of the repair material were initially determined taking underwater anti-dispersibility and fluidity as the primary design indicators, and the setting time, mechanical properties and bonding properties of the repair material were studied.In addition, the steel plate insertion method was used to imitate the concrete cracks, and the mechanical properties of the repaired concrete were studied.Meanwhile, the fast setting mechanism was analyzed by means of X-ray diffraction(XRD).The results show that the new type of environment-friendly repair materials has good fluidity, excellent underwater anti-dispersibility, adjustable setting time, moderate strength and good bonding behavior, which is expected to applied in the rapid repairing for underwater concrete cracks.

Key words: underwater repair material; concrete crack; rapidly solidification sulphoaluminate cement; underwater anti-dispersibility;